Unroll.me is a startup with a mission to declutter your inbox by consolidating mailing lists or newsletters you like into one daily digest, called a Rollup, and making it simple for you to unsubscribe from mailing lists you'd rather not be on. I used Unroll.me to unsubscribe from 63 unnecessary mailing lists and add 15 to my Rollup. (I left two daily must-reads out of my Rollup.)
Unroll.me also helpfully suggests mailing lists and newsletters you might like. You can add these to your daily Rollup or have them delivered individually. Users can also customize the delivery time of their Rollup to Morning, Afternoon or Evening.
After two days of using Unroll.me, I've spent far less time cleaning up my inbox than usual, and it's nice to be able to unsubscribe from dozens of newsletters in one spot. You currently need an invite to join the Unroll.me private beta: to get one, sign up at Unroll.me or drop me a note with your email address (like all Unroll.me users, I have five invites to give away).
UPDATE 3/12: Unfortunately, I'm all out of invites.